boelsterli



(No Model.) 2 Sheet s-Sheetl I J. BOELSTERLI. PROCESS OF AND APPARATUS FOR ELEGTROLYZING FUSED SALTS.

No. 589,523. Patented Sept. 7, 1897.

IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII/ 'IIIII w (No Model.) 2 Sheets-Sheet 21 J. BOELSTERLI. PROCESS OF AND APPARATUS FOR ELEOTROLYZING FUSED SALTS.

No. 589,523. Patented Sept. 7,1897.

Mr Johanwfioelaw -UNITED STATES PATENT OFFICE.

JOHANN BOELSTERLI, OF NEUHAUSEN, SWITZERLAND.

PROCESS OF AND APPARATUS-FOR ELECTROLYZING FUSED SALTS.

SPECIFICATION forming part of Letters Patent No. 589,523, dated September 7, 1897.

. Application filed October 27, 1896. Serial No. 610,175- (No model.)

To all whom it may concern:

Be it known that I, J OHANN BOELSTERLI, a citizen of the Republic of Switzerland, and a resident of Neuhausen, in the Republic of Switzerland, have invented certain new and useful Improvements in Processes of and Apparatus for Electrolyzing Fused Salts, of which the following is a specification.

My invention relates to an electrolytic process and apparatus, and particularly to that class employing molten electrolytes from which are obtained directly the metals, more especially metals of the alkalies; and the object of my invention is to produce in connection with my improved process a simple and cheaply-constructed apparatus that will give a good yield for a given current;

Referring to the drawings, in which similar letters of reference indicate like parts, Figure 1 is a longitudinal section showing an alternate arrrangement of cathodes and anodes. Fig. 2 is a cross-section of the same, the cathode being partly broken away. Fig.

'3, partly in section, is a form in which the cathodes are grouped around the anode. Fig. 4. isa plan of the same. Fig. 5 is a similar view, partly in section. Fig. 6 is a cathode in section, showing its position relatively to the surface of the electrolyte- Fig. 7 is a crosssection of a collector and separator for the metal formed at the cathodes.

A cast or wrought iron vessel a is placed over a suitable hearth and contains the canstic alkali that forms the electrolyte when melted by the fire on-the hearth.

The cathodes b are preferably of metal and have rounded or pointed ends thatdip just below the surface of the electrolyte, Fig. 6. This form of end for the cathodes actsas a gatherer or assembler of the large globules of metal that float on the surface of tbeelectrolyte during the electrolytic action, and when they come in contact with these rounded or pointed ends they hang to them and can then be easily skimmed from the electrolyte.

The electrodes, Figs. 1 and 2, are provided with extensions c, that are bolted by means of bolts 0 to rods or connections 0 depending from cross-bars f and f, and said connections are held iii-position by means of pins or any other suitable fastening devices. (Not shown.)

I provide the anodesc, which dip quite deeply into the electrolyte, with a sheath or envelop d somewhat larger than the electrode and open at top and bottom and extending above the surface of the electrolyte, which serves to conduct the oxygen formed at the anode above the surface to the open air or a suitable collector, if so desired,in which latter case the upper ends of such sheaths are closed and provided with leading-01f pipes. The sheaths (1 thus confine the oxygen generated at the anodes and compel it to rise to the surface in a confined isolated space, which preventsit from bubblingup through-'the electrolyte and coming into contact with and reoxidizing the metal floating on thesurface around the cathodes. 'lhe sheaths 'are made of metal, as iron, or other material, and are insulated from the anodes bygan insulating substance e, such as asbestos, which is'placed in a channel or notch at the top of ashoulderf n, rising from the anode, the sheaths being suspended by a bracket or strap a, hung-in the insulated recess of the shoulder In Figs. 3 to 5 I have shown a method of suspending-the anodes around the cathode.

and are rendered vertically adjustable by 'ineans of thumb-nuts screwed onto the upper threaded ends of the cathodes, which also forms a shoulder s, that rests on the outer ends of the rods 1 and prevents the cathodes'from dropping out of the perforation. f Each suspended cathode is connected to the other terminal of an electric generator.

The guard or sheath (1, which conducts the oxygen to the surface, surrounds and is some what larger than the anode, is provided with brackets s, insulated from the anode by a layer or facing of insulating material e, and rests on the shoulder n.

The metal collected around the cathodes is removed to one side of the bath and is run off or skimmed off and poured into a separator, Fig. 7, which is a cylindrical metal vessel '11, having a rounded or conical bottom in which there is a central perforation l, closed by a pin 70, terminating in a handle k above the vessel. A second handle m, attached to a collar which surrounds and supports the vessel '5, facilitates manipulation. This vesselor separator, being nearly filled with metal skimmed from the electrolyte, is allowed to stand a suflicient length of time to cause the separation by gravity of the metal from the electrolyte which was taken up with it during the skimming. The pin 70 is then removed and the electrolyte allowed to run out into a vessel a, after which the pin 70 is pushed back into place and the metal molded for market. 4

Having thus described my invention, what I claim as new therein, and desire to secure by Letters Patent, is-

1. The process, which consists in electrolyzing a fused alkali-metal salt and liberating the alkali metal exclusively at the surface of the electrolyte, substantially as described.

2. The combination with an anode having a gas-conducting sheath insulated and suspended therefrom and a supporting-rod therefor, of a spider supported and insulated from said rod, whose arms support the cathodes,

and means for vertically and horizontally adjusting said cathodes, substantially as set forth.

3. The combination with an anode depending from a supporting-rod and a sheath in sulated from, surrounding and depending from said anode, of an insulated spider on said rod, metallic cathodes suspended from said spider-arms adapted to have surface contact with the electrolyte, and means for verticallyand radially adj ustin g the cathodes, substantially as set forth.

In testimony whereof I hereunto sign my name, in the presence of two subscribing wit nesses, this 2d day of September, 1896.

J OHANN BOELSTERLI.

Witnesses:

H. LABBART, E. BLUM. 

